Railway braking apparatus



May 28, 1935. H. L. BONE 'HAL 2,003,035 Q RAILWAY BRAKING APPARATUSFiled Feb. 17, '1955 2 sheets-sheet 1 THE/12 ATTORNEY Y Patented M ay28, 1935 n Y l 2,003,035 RAILWAYBRAKiNG APPARATUS v lHerbert L. Bone,`Swissvale, and John W. Logan, Jr., Wilkinsburg,` Pa'., assignors 'to TheUnion Switch t Signal Com pany, Swissvale, Pa., a

corporation of Pennsylvania l n Application February 17, 1933, SerialNo. 657,210

12 claims. iol. 3034-20) t Our invention relates to railway brakingappaA v A bar A1.V The oneend 'la of therlever 'I is likewise ratus, andparticularly to braking apparatus of the type comprising wheel engagingbraking bars located beside a track rail, and movable toward;

andv away from Athe railinto brakingand nonbraking positionsgiMor'eparticularly,` our invention relates Atoiapparatus of the type describedwherein the braking barsare arranged to bev moved 'to theirA brakingpositions by means'of one or more fluid pressure operated motors, Vandto be restored to their non-braking positions by l suitable biasingmeans suchxas gravity.

Specifically, our invention relates to means for V controlling thefsupply of Huid pressure to, and,

exhaust of uid pressure from,`the fluid pressure motor or motors ofbraking apparatus of thel type described 'when the braking apparatus isto be utilized in connection with a duplex pressure fluiddistributionnsystem such as is disclosed and claimed in an application*for Letters Patent of theUnitedV States, Serial No. 639,434, filed byHerbert Lj. Bone, on October 25, 1932, and, one object of ourA inventionis to improve and simplify thel control means disclosedV in the saidBone appli?Y cation.,

thedescription proceeds.

Wewill'describe two. forms of apparatus ein'- bodying our invention, andwill thenv point'out Vthe novelfeatures thereof in claims. Y In theaccompanying drawings, Fig; 1 i'sadiagrammatic VView illustrating oneform ofapparatus embodying our invention. Fig. 2 is a similar viewillustrating a modified form of theapparatusjshown in Fig. '1. l j

'Similar reference characters refer to 'similar parts inzboth views. Y

Referring to the drawings, the reference character I designatesonevtrack rail of a stretch lof 40" railway track, which track rail, ashere shown,

is secured to a rail support 2 mounted on an adjacent pair of the usualcrossties 3, only one crosstie being visible in the drawings.Associated'with the. rail I' isa car retarderV comprising .two brak-ling bars A1 andAz located on vopposite sides of theV rail. Each` ofthese braking bars comprises, as

usual, a brake beam 4 and abrake shoe 5.

The braking bars A1 and A2 are arrangedto be moved toward and away'fromthe rail I through the medium of a lever 5 which is pivotally mountedatone end on a pivot pin 8 carried by the rail supportl, and a lever 'lwhich is .pivotally mounted intermediate its ends'on the pivot pin 8.The n Y positions. ,It will be obvious thatwhenthe ,brak` .A

ing bars are moved to their braking positions, 65

klever Sis inclined upwardly avnd'extends away Other ,objects ofAourinvention Awill appear as from the rail I', and is provided in itsupper surface with a groove IiEl which receives-the braking 'e .inclinedupwardly and extends away fromthe rail I at the opposite side of therail from`the level-.,S, and the other end Y'Ibof the lever'l is in-J'5f' clined downwardlyV and extends away from the Vrail i below thelever 6. The end .'I8L of the lever 'l is provided in its upper surfacewith a groove lc, similar tothe groove Ia in the lever 6, which Y The.parts l0 groove receives the brakingbarAz.1 y are so arranged Yand soproportioned thatif the. outeror free ends of the levers andf'Il are'moved apart, the brakingbars will be moved toward Ethe' rail I intotheireifective or braking positionsQ- When the braking bars occupy their.brakingpo- 15,'

sitions,*the'brake'shoes 5 will engagethe oppositeV side faces of acarwheeltraversing rail I, and will v Y retard the speedof the car. Thecenter of grav-V.,y ity of the lever Band braking bar A1 is consider'rably to the right of the -pivot lever will normally tend to rotate Vin`a clockwise direction about the pivot pin.` Similarly, the cen ter ofgravity of. the lever 'I Aand brakingbar A2 is to the leftof the pivotpin 8, so that Athis ,leverv will normally tend to rotate in acounter-clockfv .255*

wise direction about the pivot pin. Itwill be ap#` I parent, therefore,that when no forceis applied tothe free ends of the levers 6 and I to nlove/ them apart, the free ends of theselevers will move toward eachotherVthereby moving the braking 301 bars to their ineffective ornon-braking positions Y in which they are illustrated in theV vdrawings.

- The levers B and 1 are arranged to .be moved'` apart to move thebraking bars to .their braking positions by means of afluid pressuremotor M .35j4A comprising al cylinder 9 containing a'reciprocable pistonIi! which drives a piston rod II; Thecyl` inder Q is pivotally connectedwith the free. endl of the lever 6 by means of trunnions' I2 formed l onthe side of the cylinder and extending through bifurcations VI3 formedon the lever 6, while the piston rod Ilfis connected at its freev endwith the free end 'Ib of the lever 'I by meansof an adjustable eyebolt I4 and. a pivot pinfI5'. Fluid pressure maybe admitted to the cylinder 9lbev45V tween the upper end of the cylinder andthe pisf ton It! throughan', opening I6 which is threaded ,y l

Vto receive a pipe Il. AWhen iiuid pressure is admitted to the cylinderS'through the pipe I1 and.

Opening 95, the. piston I U will be forced,r down-1 '5 0 n wardly andthecylinder S up-wardly',thereby,sep-x grating the levers 5 and` 1, andhence moving the Y brakingjbars toward their eiective Yor braking pinsso that this l20"# yrality of other similar units, disposed atspacedintervals along the bars, substantially as shown in Patent No. 1,927,201issued to Herbert L'. Bone, on Sept. 19, 1933, for Railway brakingapparatus. It shoul-d also be pointed out,.that as a general rule, thecar retarder will consist not only of K braking bars associated with'4one track rail, as shown in the drawings, but also of other similarbraking bars associatedv with the-.opposite track rail as well, thelength of the braking bars asso-- ciated with both track rails beingdetermined` by the speed and the weight of the carsto be retarded,'thelengths of the cars, the number oi wheels on the cars, etc. Y The motorM is controlled by three magnet valves designated by the'reierencecharacters V1,

valve ,stem t8V biased to anlupper position byY means of a spring !9andprovided with a winding 20 andan armature 2 I., When valve V1 isenergized, as shownV inV the" drawings, valve stern |53 of this valvemoves downwardly against 'the bias temi 'Ihis loviT Trend of thecylinder is supplied with'fluid presexerted by the associatedy springi9, Vand under 4o.f11pper .end of the cyundelf from atmospherelV Whenvalve V2 then disconnected from pipe 2l, so that thesupthesefconditions,apipe Y22 which communicates with pipeV I1 is connected Y withatmosphere through a port 23,'thus connecting the region of cylinder 9between piston Ell land the upper 'end of the cylinder with atmosphere.WhenL valve Vl is deenergized, however, valve stem i8 of this valve ismoved upwai'dlyby springy I9, and pipe 22 Yis then disconnected fromport23, so that the region of cylinder 9 between piston in and the isthen disconnected e is energized, valve stem I8 of this-valve' movesdownwardly, anda pipe v24 which constantly connnuiiicates with the pipeV22 is then connected 'with a pipe 25 forming part .of a low pressuredistribution syspressure` distribution system is constantly. suppliedwith duid' pressure, usually air, lfrom a ,relatively low pressuresource' not shown in thedrawings, and it :follows that when valveV2 isenergizedthe region of cylinder 9 be tweenpistonjand the( upper end ofthe cylinder is supplied; with fluid pressure from the low pressuresystem. Whenvalve V2 in deenergized, however, pipe 24 is disconnectedfrom pipeA 25, andis connected with a pipe 25 which leads When` Valve V3is energized, valve` stern i8 of this'v'alve moves downwardly, and vpipe26 is then connected with a pipe 21 forming part of a high pressuredistribution sysf tern, which latter distribution system is con--stantly supplied withiluidpressure, usually air,` from a relativelyhigh pressure source.

1t will be seen, therefore, that when valve V3 is energized and valve V2.is deenergized, the region of. cylinder 9 betweenthe piston leand theupper4 sure from the high pressure'system. When valve V3 is deenergized,however, valve stem I8 of this valve'moves to its upper position, jandpipe 26 is 'ply of iluid pressure from thehigh pressure sys'- tem tocylinder 9 is cut off.

The pressure ofthe uid in the low pressure system may be Vmaintainedatrany suitable pres- ;sure, but for purposes of illustration, we willassume that this pressure is maintained at approxisure responsivedevicesP20-3 and. PTO-8"; each comprising a Bourdon tube 28 connected to thepipe l'l, and hence subjected to the pressure of the iiuid in the regionof cylinder 9 between the piston l and the upper end of the cylinder.vEach Bourdon tube 28 controls two contacts The pressure responsivedevices P2-3 and P'm-m are so constructed that they will operatesuccessively as the pressure of kthe fluid in the region of cylinder 9between piston i 0 and the upper end of the cylinder increases. Forexample, for all pressures belowY 20 pounds per square inc h, Vcontact`29---29a of each of these devicesvis closed.'V If the pressurevexceedsf20 pounds per square inch, however, contact 29-29e Vzzand V3,respectivel, and each'cornpris'ing. a

sure responsive device Flo-89 is adjusted to open itslcontact 29--29eVat 7 0 poundsl per square inch, and to close its contact-ZJ-ZS!b atpounds per square inch. Of course,` these 'specific pressures i are not,essential; but are only mentioned for purposes of explanation. Y

The ,valves Vare further controlled by means of two slow-releasingrelays B and C of the-usual type, and by a manually operable lever L,which lever also controls the relays B and C. As here shown, the lever'L is capable of assuming vfive positions, indicated by dottedlines inthe drawings, and designated by the reference characters p1 to p5,inclusive. Operatively connected'with the lever L are a plurality ofcontacts designated by the reference characters 30 to 36, inclusive,-

with exponents corresponding to the position, or positions, of the leverin which the associated contact is closed. Forexample, contact 3ll5isclosed in thepl position of the lever. In similar manner, contact 334-5is closed in the p4 position of the lever, the p5 position, and anyposition intermediate these two positions.

Lever L will usually be located at a point remote from the brakingapparatus, as in the con? trol cabin ofy a classification yard carretarder system, and will be connected with the braking apparatus bymeans of line wires extending from the control' cabin to the brakingapparatus.

As shown in the drawings, lever L occupies its p1 or off position. Underthese conditions, a circuit is completed for relay C at contact 321,-?1of lever L, and current flows from a suitable source,

such as a battery D, through wires 3l, 38 and 39, contact 321-2 of leverL, line wire 40, thewinding of relay C, wire4i, and. line wire 42 backto-battery D. Relay C is therefore energized. All circuits ior relay Bare open, and this relay isA accordingly deenergized. The valves V2 andV3 are both deenergized, but valve V1 is energized over a circuit 'whichpasses from battery D through wires 31, 38, 39, 43 and44, contact 341 oflever L, line wire 45,.back contact 46-'4 6a of relayB, wire 41,.winding 20 of valve V1, wires 4 8 and 49, and line wire 42 back tobattery'D. Since valves V2 and V3 are both deenergized, the supplyv ofiiuid' pressure to motor M from both the low. and high pressuredistribution systems is cut oil,

and since valve V1 is energized the region of cylinderzfs forces piston.HJ

inderr ofp'mo'tor--M=between1pistonIMJ and "the nppernd .of therlcylinder :is fuonnected with iatmosphere. The .-'braking vbars #aretherefore 'he'ld in .the ineieotive ltor'.non-:braking positions @bygravity. Y

in --explaining the operation fof 'thefapparatus 'as-:a whole, rwewillnrst Tassume:that itheeoperator -wishes ato :maken comparativelylight brake application. To ido this he :moves .-'lever TL :to itspzyposition, Vthereby opening contact 1341 of fthe lever :and :closingcontact i362. ...'Ilhexiopening bof oontacti341 :interruptsthercirci'tWhichwvaszpreviouslynlosed for valve "V1 rat :this-.contact,r 'and valveA V1 thereforebec'omesrleenergized fand dis-Vconnects pipe 22 yfrom pipe -23,*thus disconnecting the'regdonaoffcylinderc 'cfimotorLM between piston-'Hl :the aipperffend-fof' the.cylinder from atmosphere. The closing :o'f contact362 of lever'Licompletes ia circuit fiorvalve W, :and :current flowsffrom .battery Dthrough vwvires13171:,"38,il-9,243, `M5511 'Contact '229---29at of :and51, contact 2362 of 'lever L, line .wire152, pressure :responsive deviceP-39;.'Wires 4253,154, '55.'and 5 6 Wind-:ing 20. .of valve .V2 wirewill, A:and-'line wire 42 back 'to battery D. Val-ve V2 therefore:becomes Aenergized Yand connects :pipe 24 wi'thzpipe 25, .sothatfifluid .pressure rfrom the Vlow :pressurevdistribution `system isnew jsupplied to the upper fend of cylinder@ o'f motor'M.Thefluidfpressureithusfsupplied'to cyldownwardly and cylinder :9yupward-1y, lthereby ,movingithe'lfbrakinglbars towardItheir'.:braking:positions. :soonas the pressure in 'cylinderiz'sincreasesito U1-pounds A'per inch, contactZtl-291ab of 'pressureyresponsivedevice P20-3 v`opens rand 'interrupts .the rcircuit justtraced Afor y'valve V2.. yal-Ve Wkthen -becomes rleenergized'fan'dcutsoiit'he supply 'of uid pressure to :cylinder .i9 until the pressure`in the cylinder Vhas again decreased to 120 V'pounds per square inch,whereupon*contact1'29-29'n again closes and reestablishes :the 4circuitor fvalve V2. If .thepressure .ofzthex'uid '.inthe upper end of cylinder9'anow increases to .30;.pounds Iper 'square inch y:for any "reason,'contact '.29-'29bofpressure 'responsive ldevice P20-3 'will becomeyclosedV and will Vcomplete :another .Icircuit .for valve V1, this:latter circuitxpassing :from .battery 'D through wires 31, 3,8, 39, 43,44, SlandSI, contact362of lever eL, line wire 1.52, Contactr1'2Sl--i2'9bfoi 4pressure responsive Vdevice *'.PZU-gwire 551, 'hackcontact.

n lli-46a of :relay B, Wire'l'll, winding '20'of valve Vewiresi and 49,and lineswire 42 back to batteryD. Halve 'V1 will .therefore becomeenergized and ywill vent iuid from the upper `end o'f'cylin'` der 5 toatmosphere untilthe pressure of the fluid in this iregion of the.cylinder Iagain -de creases rto 4pounds p'ersquar'e inch, at which timecontact J-29b of pressure responsive -device P-3 will open andWilldeenergize valve `V1. It will :be seen, therefore, that when VleverVLY occupies 'its p2 position,v the braking barsv will -be held in theirbraking position by apressure of ibetween I2() vand 30 pounds per squareinch.

:'If .the operator desires to make va Amorepowf-zr'- ful brakeapplication,:hewillmove lever'L `to its pfffposition. This movement ofthe `lever interruptsthe circuit which Was'previou'slyclosed 'for theslow-releasing relay C'rat contact 3214er lever -L, and las a result, assoon as va time interval equal to thereiease Jtime of this remy hasexpired, this relay will releaseA its armature, Ytliu's opening itsfront contact T5S-'53a vand closing its back contact Sil-58h. Theoperation fof these contacts under these conditions, however, will haveno eilecton the `remainderof the.apparatus.`

The movement-:f 'leverL toits. p3 position -also''in- Y cuit :for"thevalve V2,'this latter circuit-passing fromibattery `DIthrou'gl Wiresi3l-and-38f eontact 3'! 3f.:of..1'ever;L, line wire'59, Wires'lilland-'56,'win'Ad-nv ing llfof' valve V2, Wire 49, arid line-Wire 42back to fbatteryD. It'will lbeinoted 'thatthis latter cir-1 cuit iscontrolle'clsolelyoy contact' '3|3. of levrflli, so that when thiscircuit `.becomesclosedgitfwill remain .-'cl'os'edras lo'neraslever 'Lremainsin its p3. rpositio'n. When this*`clrcuit' foecomes f'clo's'clvalve V2 will ofcourse'fbec'omeenergized, and iv'vill admit fluid 'fromthe low. 'pressure' distribution system tothe upper end-'ofcylinderfl'of noto'r f; and --it folio-Ws,` therefore, .thatv'vhenJeverfL cupies.its 'p3 positionjthe-braking bars *Willbe held .iin their braking.position lby Vthe r`f ull pres?" sure 'of .the low Vpressure source. --2

Ifxa still higher-braking force is desired, the operator will Jmovelever vLvrtoits p4 pofsit'ion When he does this," all circuitspreviously traced'l forthe valves V1 and V2 will be interruptedg'andifbacknentact5B-581 of relayC is thenclosed, as "will be thecase if thelever is movedto-fitsp4 position after remaining `in itslpfposition'flong enoughlto causev relay C lo-'release its'aiinaturavalve V? will immediately becorneenergized Yand will admit Fluidpressure to the upper' v en'd' lof cylinder 5 of motor M from` the high"pressure sys:-

tem, the circuit'fcr valvevunderthes vcondi-v tions vpassing A.frombattery D through-Wires 3'7, 38, 39, '43, 44' and 50, Contact354fo`fflever'L, vline Wire 7lgcontact -29-2llafof pressureresponsive'device P70459, Wire 62, back Contact 58;53bfof relay fC, WireSS, WindingV2l) ofvalvevanldlihe Wire '42 `vback AiIto ibattery D.- If; however,when;

of relay C .is stilllpicked'up is moved to its .p4 position from its "p1or valve V3 will not Furt `lermore,underv these/latter conditions; s

long as :front conta/ct'SB-"Saof relay C remains closed .afterlever'ffLh'as reached its position',

valve. v2 win-:be .energized 4over a Circuitwhich passesrombatteryDthrough wiresfl'ji, 39, 43,"

Menara-.contate is 54er ylever' L, une wire :s l, een#- l tactzsafdfpressure responsive device PFU wire 62,` front-iContact'fitr-51821*ofrelay C, wir ana-56, y"windingfz'ujof valve v2, wire-fda an wire 1'42back -to battery' D. becomes energized, iuidpr'ess underv 'theselatterfconditions AWill be suideient'ly pressure offtheV low .pressurelsvfsz;

terne/before valve Vbecorn'es energized and admits fluid to the k-mot'orj'from thefhigh pressure 'sy'.sff the iiuid 'incylinder .9 new increasesto "Z0 ,pounds-persquare'v'inch tem. "When the'pressure o fpressuresystem will approximately `5G pounds per square inchfon inchforany reason, contact 29--29b of pressure supplied to whereupon valveover the previously traced circuit including 'eonresponsive `deviceP20-20 will become closed, and will complete a circuit for valveV2,passing from batteryl D through wires 31, 38, 39, 43, 44 andS,contact 354 of lever L, line wire 6 I, contact 29-29b of pressureresponsive device PTO-2, wires 54, 55 and 56, winding 20 of valve V2,wire49, and line wire 42 vback to battery D. Valve V2 will thereforebecome energized, lthus connecting4 pipe '24 with pipe 25, and since thepressure in the upper end of cylinder 9A of motor M 'will thenY beconsiderably above the pressure of the iluid in the low pressure system,fluid will be exhausted from the motor into the pipe 25;V VAs soon asthe pressure ofA the uid again decreases to pounds per square inch,contact 29e-2920i pressure respon-Y sive device P'0-89 will open andwill deenergize valve V2. It will be apparent, therefore, that whenlever L occupies its p4 position, the braking bars will be urged totheir braking positions by a pressure of between '70 and 80 pounds persquare inch. The closing of contact 334-5-of lever L, when lever L ismoved to its p4 position, completes a circuit for relay B which passesfrom battery D through wires 31, 38, 39 and 43, contact 334-5 of leverL, line wire 64,A winding of relay B, wires 65 and 4|, and line wire 42back to battery D. Relay B will therefore .become'e'nergized but theenergization of this relay will have no effect on the apparatus unlesslever B is subsequently moved to its p1, p2 or p3 position to decreasethe pressure of the iiuid supplied to thecylinder 9 of motor M, whichoperation will be described in detail hereinafter. y

We will now assume that lever L occupiesits p4 position, and that theoperator moves itto its p5 position. Under these conditions, all cir-4cuits previously traced for Athe valves V2 and V2 will becomeinterrupted and another circuit for .valve V3 will become closed, thislatter circuit passing from battery D through wire 31, contact 395Y oflever L, line wire 66, back contact lill-58b ofY relay C, wire 63,winding 20 of valve V3, and line wire 42fbackrto battery D. Valve-V2will therefore become energized and will subse.`

energized as Vlong as lever` L position. VFluid pressure from quentlyremain remains in itsvp5 Ythe high pressure syster'n will therefore nowbe cylinder 9 of motor M, so that thev braking'bars will exert 'theirmaximum vbraking force. e Y

, If the operator, instead of movinglever L toY its p5 position from itsp4 position, Vmoves it directly'to its p2 position from its` p1 or `p2position, the apparatus will then function in the same manner as whenthe lever was moved directly to its p4 position from its p1 or ,p2position, up to theV point where relay C releasesA its armature, V3 willthen become energized tact 305 of lever L and relay C.

We will next assume that vthe operator has moved lever Lto its p5position to cause the backjcontact 584-581 ofV braking bars tolexert'their maximum braking` force, and. that he Vnow wishes to restore thebraking bars to their ineffective or non-braking positions'. He'willtherefore more lever L `from its p5 to its p1 or o this, the circuitwhich was previously closed for valve V3. at'contact 305 of'lever Lvwill become interrupted, and valve V3 will-therefore become deenergizedand will disconnect cylinder 9 of motor Mv from pipe 21, so that thesupply of uid pressure from the high pressure system will then becutoff. Furthermore, vwhen the operator moves lever L to its p1position, the circuit which was previously closed for.v relay B. atcontact 334-5. of lever L will also become interrupted, and relay Bwill'therefore become deenergized. Due, however, to the slow-releasingcharacteristics of lthis relay, thisrelay will not immediately releaseits armature, and during the `time interval while the armature of thisrelay remains closed Aafter' the rleverreaches its p1 position a circuitwill be closedfor valve V2 which circuit passes from battery D throughwires 31, 38,v 39, 43Y and, contact 341 of lever'L, Wire 45, -frontvcontact ,46446b of relay B, Wires 55 and 56, winding 20 of valve V2,wire 49, and line wire 42 back to battery D. Valve V2 will thereforebecome energized and will connect motor Mwith pipe'25,

and since Ythe pressure of -the vfluidin the motorsure of the fluid inthe low pressure system, and

it will beseen; therefore, that aV large percentage of the fluid in themotor will be vented into thelow pressure system for use at a latertime.` When relay B nally releases its armature, valve V2vwill,vofcourse, become deenergized, and valve V1 will then become energized overthe previously` describedfcircuit,including back contact 46-462 of relayB and contact 341 of lever L. When valveA Vlbecomes energized, theremainder of the uid in the motor'will Vbe vented to atmosphere,- Vthuspermitting the braking bars to return-to their ineffective ornon-braking positions. The movement ofv lever L to its'p1 positionalsofcompletes the previously described circuit for relay C includingcontact 321-2 of lever L, so that position. When he does relay C nowbecomes energized'. The energiza-'V tion of this relay under theseconditions, however, `has no effect onthe remainder of the apparatus.When the braking bars reach their nonbraking positions, all parts arerestored to the positions in which they are shown inthe drawings.r i 1If 'the operator, instead of moving lever L from its p5 position to itsp1 position, moves the lever from its m5 toits p2 positiorrvvalve V3an'drelayr B will both-become deenergized in the man-v ner just described,but under these conditions' during the interval of ,time required forrelay B to release its armature and open its front contactafter itbecomes deenergized, valve V2 will become energized over the previouslydescribed circuit for' this relayincluding contact 362 of lever L,contact 29--29b of pressure responsivedevice P20-30,'

and front contact lhi--IIGb of relay B, and when relay B finally opensits front contact andv closes its back contact, valve V1 will thenbecome energized over the previously described circuit forf valve Vlincluding contact 362 of lever L, contact 2,3.-29b of4pressure-responsive device P20-3 and` the apparatus for the remainderof Athe movel back contactAB-.d .of` relay B. VValve V1` will thenremainenergizeduntil the pressure of the fluid. in themotor decreases to 30rpounds per squareinch. It will beseen, therefore, that underthe'condtions just described, the Vfluid in motor M Willbe vented intothe low pressure.' distribution system until the pressure decreases tosubstantially. the. pressure of the low pressure system'after which thefhud in ther motor will he vented to `atmosphere until the pressuredecreases suiciently to cause contact 29'-29.b of pressureresponsive.devicesP20-30 to open and deenergize valve V1, whereupon thepressure responsive device P2-030will. operate to energize valve V1 or ivalve V21in the same manner as when lever L is moved to its i12-positionfrom its 'p1 position. 1

While in the foregoing, we have described the operation of theapparatusfor only a few oi the f possible movements of lever L, the operation ofments of. lever L'is similar tothat which has ale ready;r beendescribed, and it is believed, therefore, that this operation will beunderstood from an inspection' of the drawings'and from theforegoing/Without the necessity for describing it in detail here.

It should be pointed out that with the apparatus constructed as shown inFig. l, the relays C" and B may be located either at the control pointor at the braking apparatus without materi-ally affecting the circuitsfor the valves V1, V2 and V3, or the operation of the apparatus.

--Referring now to Fig. 2, in the modified form ofl apparatusy hereshown, the relays C and B areV 2 intended to bie located at the controlpoint, and

rectiers have been provided to decrease the number of line wiresrequired between the control pointV andl the braking'apparatus.With'tlie apparatus arranged as hereY shown, two addin tional. contactsliti and 'H2 are required on the lever. L, these contacts being vclosedin the pLk andfp?. positions of the lever, respectively.

The operation of the apparatus shown in Fig. 2 is as. follows: Whenlever L occupies its p1 or off "YI-position, in which position it isshown in the drawings, valves V2 and V3 are both deenergized,

andi valveV1 is energized over a circuit which passes from battery Dthrough wires 13, 'M 'and 15, Contact 3131 of lever L, wires 'l and Tl,rback `.contact 4.E.-46 a of relay B, wire 18, line wire le,

anasymrnetric unit 8B in its low resistance direction, winding 20 ofvalve V1, wires 8l and 82, line wire'83, and wires 84 and 85 back tobattery D.

Since valves V2 and V3 are deenergized, the supv ply;A of iiuid pressureto therupper end of cylinder 9 of motor Mv from both the high and lowpressure distribution systems is cut off, and since valve. V3 isenergized, the upper end of cylinder 9 is connected with' atmosphere atport 23. TheV braking bars A1 and A2.. are therefore held in theirineffective or non-braking positions by gravity. Furthermore, sincecylinder Sis vented to atmosphere, the contacts 29+29sof. the pressurere` lsponsive devices P20-30 and P20-00 are both closed,

"and the contacts 29--2!lb of the pressure re;-

sponsivev devices P20*lo and P0080 are both open.

Relay-B is'deenergized, but relay C is held' energi'zed over a circuitpassing from a battery E through wire 85, winding of 'relay C,wire 8e,contact 321-2 of lever L, and wires |02 and 81 back to battery E. f f

We will now assume that the operator moves lever- L-from its p1 to itsp2 position Ycause the braking bars of the braking apparatus to exert acomparatively light braking force. This move' lil.

battery D. Valve V2. will therefore become'ener-i..

gized vand will admit fluid pressure vfrom the low pressure system tothe upper end offcylin-f der 9 of motor M, thuscausinggthe brakingbars.Y'

to move to their braking positions. When. the. pressure of. the uid incylinder 9 increasesto 20 pounds per vsquare inch, contact'Z'SI-Ne of;pressure responsive device P2040 will openand will deenergize valve V2,thus. cutting off the supply of :fluid pressure to the car retarder op.`erating motors. If the pressure of the fluid in cylinder 9 now increasesto 30 pounds. per square inch, contact 29-290 of Vpressureresponsive.de.

vice P20-30 will become closed, and another cir--l cuit for valve V1latter circuit passing from battery D through wires 13, 74 and l5,contact 362 of lever L, wirel 88, linewire 89., asymmetric unit 9| Yinits low resistance direction, contact 29-29? of pres.-

sure responsive device P2040, line wire 94,YCon= tact H2 of lever L,wiresjjand VVLback conf..

tact lid-45a of relay B, wire 18, line wire '19,

asymmetricunit 86 in itslow resistance direc.A tion, winding 2Q- ofvalveVl, wires 8l and 8.2,'

Y and 85 backtoI bate.Y tery D. ValVeV1r will therefore become enen-gfrom cylinder 9,. to: previously described. the uid in cylinder linewire 83, and lwires 84 gized and will vent uid atmosphere in the mannerAs soon as the pressure of 9' again decreases below 30 Vpounds persquare inch, "contact 29 28b of pressure responsive def. Vice P20-30will become'opened and will-inter-v rupt the circuitjust traced forvalve V1., sothat this valve' Willthenl become deenergized, thus` willthen be completed, this.y

preventing further escapeof fluid from' cylind 9 to atmosphere.

shown in Fig.2

It will be apparfrli?,v theresV fore, that with the apparatusVVconstructed as.r when lever L occupies its p2` position, a pressure ofbetween 2.0 and 30 pounds' 1 per square inch will be maintained incylinder 9 of motor M in substantially the same ner as itv is maintainedbetween thesetwo` pressuresgwhen lever L occupies a corresponding,`

position with theapparatus constructed as shovvp in Figi. l. v

We will next assume that the operator moves,

lever L from its p2 to its p3 position toincreasel the braking forceexerted by the braking bars,

Under these conditions; the circuits previously traced for valvesVl. andV2 including Contact 362 of lever L- will both become interrupted at*this contact, and valve V2 will now becomeenergized over. anothercircuit which passes 201.11. battery D through. wire 73, contactl3 oflever L, wire 96, line wire. ,91, wire 92, windingZQ* of valve V2, wire82,\line wire 83, andwires 84 and 85back'to battery D. It will be notedpressure responsive contacts: and itwill ,be apr` u energized. aslonglas leverv L remains. in its p31 parent therefore that valve V2 willnowremain i toA 70 i. .that this circuitdoes not include any oli` the.

unit "S8-,in its low kresistance from .the :low `pressure source. willconstantly be supplied to -cylinder 9 of motor M to hold the brakingbarsinftheir braking positions. VThe movement of lever L `to its p3positionwill also interrupt Ythe circuit which was previously closed for relay Cat contact 321-2 of lever L, so that relay C will now becomedeenergized; The deenergization of this relay under these conditions,however, will have no effect on the remainder ofthe braking apparatus.

We will next assume that the operator moves lever Lfro'm its p3 to itsp4 position-to cause the lbraking bars to exert'a still higher brakingforce.l .This movement of lever L will interrupt the circuit which waspreviously closed for valve V2' at contact 3|3 'of lever L, and willcomplete a circuit for valve V3, which latter circuit passes fromybattery .E throughv wires 85-and 84, line wirej83,winding 20 of valveV3,

direction, line wire 19, wire 99, rback contactiii-Eb of relay C, wire90, contact 194 of lever L, line wire 94, contact 29--29ab of pressureresponsive device P30-3,

an asymmetric runit |91 Vin its low resistance direction,.wire 89,contact 354 of lever L, and wires |02 and 81 back to battery E, Valve V2will therefore become deenergized, and vvalve V3 Will 'becomeenergizedso that iluid pressure will nowy be` supplied to cylinderl 9 of motor Mlfrom the high pressure system. Fluid pressure will continue-.to besupplied to cylinder 9 of motorV M' under these conditions until thepressure in the cylinder reaches '70 pounds per square inch, atV whichAtime ycontact 29--29a of vpressure reilsponsivek device 'P30-33 willbecome opened and will interrupt thecircuit just traced for valve V3..Valve V3 will then become deenergized, thus cutting off the supplyof'fluid pressure to cylinder 9. If the pressure in cylinder 9 nowincreases-to 80'pounds per square inch for any reason,` so that contact29-2 9b of pressure responsive device'P'm-30 becomes closed, anothercircuit for valve V2 will become completed and current will flow frombatteryEfthrough line wire 83,- wire 82, winding wire 92, contact29-291of pressure lresponsive device 1333-30, asymmetric unit IUI in itslow resistance direction,line wire 89, Contact 354 or' leverk L', andwires l92 and 81 back to battery E. Valve V2 will therefore becomeenergized, and since the pressure of the fluid in cylinder 9 will thenbe above that in the pipe 25, fluid will be vented into this pipe untilthe pressure in cylinder 9 decreases suiciently `to cause contact29---29b to .,zopen and deenergize valve V2. It will be seen,

therefore,that when lever L occupies its p4 posi- K tion,` theiluid inthe car-retarder operating mo- 305 of lever L, andwirev`-braking-force.`

tors will be maintained at a pressure of'between 'lO-and 80 pounds'persquare inch in substantially Lin Fig. l occupied its'p*1 position.

`If `the operator moves lever L from its p4 to its p5position to causethe braking -bars to exert their maximum braking force, valve V3 willbecome energized over a circuit which passes from wiresand 84, line'wire83, asymmetric unit 98 in line wire 19,`wire 99, C, wire 90, contactbattery E through Winding 20 of valve V3, its lowV resistance direction,backcoritact 58-58b of relay Fluid pressure will therefore now besupplied to mot'or'M from thehigh pressuresystem as long as lever-Lremains in its p5 position, thus causingthe braking bars an asymmetric'.

,under similar conditions in connection wires 85 Vand 84,V 29 of valveV3,

8l back to battery E.Y

to exert their maximum We will next assume that the parts are inthepositions in which they are shown in the drawings, and that the operatordesiring to make a comparatively heavy brake application,.movesle= ver Ldirectlyv from its p1 to itsp4 out stopping the lever in either of thetwo yintermediate pcsitions. `YUnder these conditions, the circuit whichis closed for valve V1 at contact 341 of lever L when lever L occupiesits p1 position, will become opened, and valve V1 willtherefore becomedeenergized and will disconnect cylinder 9 of motor M from atmosphere.Furthermore, the previously described circuit for relay Gl includingcontact 321-2 of lever L will become opened,'and the previouslydescribed circuit for relay B- including contact 334-3 of lever L willbecome closed, so that relay C will become deenergized and relay B willbecome energized in much the same manner as was previously describeddescription of Fig. l. Due to the slow-releasing characteristics ofrelay C, when this relay becomes Vdeenergized, its armature will remainclosed for a relatively long interval of time thereafter, and duringthis interval of time valve V2 will be energized over a circuit whichpasses from battery E through wires 85 and B4, line Wire 83, wire 8,2,winding 29 of valve V2, wire 92, line wire 9i, wire 93, front Contact58--5811 of relay C,

wire 98, contact 1030i lever L, line wire 94, contact .t9- 29a ofpressure responsive device P7340, asymmetric unit ll in its lowresistance direction, line Wire 89, contact 354 -of lever L, and wires.I 02 and 8l back to battery E. When valve V2 is energized, fluid fromthe low pressure systern will, of course, be admitted to cylinder 9 of'motor M, and as Was previously pointed out in connection with Fig. 1 theparts are so proportioned that the time interval during which relay` Cwill remain energized under these conditions will be long enough topermit the pressure of the fluid in cylinder 9 to build up tosubstantially the pressure of the fluid in the low pressure system. Whenrelay C finally releases its armature,

the circuitV for valve V2 will be interrupted by the openingof frontContact 58-583 of relay C and valve V3 will then become energized overthe previously described circuit including back contact 523-58.b ofrelay C and contact |04 of lever YL.. Fluid ypressure. will then besupplied tothe cylinder 9v of motor M from the high pressure Y' system.It will be apparent, therefore, that under the conditions justdescribed, iluid pressure willfrst be admitted to cylinder 9 from thelow pressure system until the pressure of the fluid in the cylinderbuilds up to substantially that of the low pressure system after whichfiuid from position. with- With the the high pressure system-will beadmitted, to.v

cylinder 9. After valve V3Vvonce becomes ener'- Y g'ized, the apparatuswill then operate in the same manner as it doesafter this valve becomesenergized ywhen lever Lis moved from its p3 to its p4 position, andthedescription of the operation of the apparatus from this point on neednot, therefore, be repeated here. v If theoperator instead ofmoving-lever L directly from its p1 to its p4 position moves it directlyfrom its p1 to its p5 position, the apparatus will function in the samemanner as has just been described, up to the point where relay Creleases its armature, at which time valve V3 will then become energizedand will subsequently remain energized over the-previously describedcircuit for this valve including back contact 58-58? C and contact 305of lever L.v

of relay A will nowA assume thatA the brakingbars havecbeen movedv tothe positions in which they `exert their maximum braking force ,-loyrmoving lever L to its 'p5' position, `and thatfthe operator desiring to'restore the braking bars to their non-braking position, moves. lever Lfrom its p5 position to its p1 position. .Under these conditions,thecircuit which is normally closedfor valve V3 atcontact, 3oflever LAwhen lever L occupies. itsppositionrwill vbecome interrupted atthiscontact, lso that valve V3 willfnow ,bef comedeenergizeddand will Ycutone the supplyof fluid pressure from vthe high pressuresystem tocylinder 9` of motor Furthermore, the circuit which is normally closedvfor relayB at contact y33??v5 of leverLfwhen lever L occupies itsY p5position ,will also become-interrupted, so that this relanwill nowbecome deenergized. When this relay Vbecomes deenergized, itwill notreleaserits armature until after theV release time for which therelay isadjusted has expired-.and as long as the armature of relay B remainsclosed, a circuit will be completed for valve V2 which passes frombattery Dthrough wires 13, Hand 15, contact 3&1 of-lever -111v Wires 'i6andl'l, front vcontactV tti-@48h-v ofl relay B, line Wire 28 of valveV2, 84 and 35 back to battery D.V Valve *V2 willtherefore becomeenergized and will connect Vcylinder 9 of motorM Withpipe 25,l and sincethe pressure of the Viluidin `cylinder 9 will then be above that in,pipe 25, fluidfrom cylinder 9 will be vented into this pipe.,v As waspreviously pointed out, the release time of relay B is so adjusted that91, wire 92, winding when Vvalve V2 becomes energized underjtheseconditions, it will remain energized long` enough to permit the pressureof the fluid in cylinder 9 to.

decrease to substantially that of the iluidin; pipe 25., When relayBfinally opens its armature, the circuit just trace-d forvalve V2 will,of cours-e, be interrupted .at contact i6-453b yof relay B, so that thisvalve will becomev deenergizedand valve Vl will then become energizedover thepreviously described circuit for this valve includingbackcontact 46-462 of relayB and contact 341 ofjleverL.y

Theenergization of valve kV1 will,l cause the remainder of the iiuid inthe cylinder 9 to be vented to atmosphere so that the braking bars Willnow return'to their non-braking positions. The move-1 ment of lever Ltoits p1 position will also .com-

plete the circuit forv relay C including contact` 321-201` lever L andrelay C will therefore become energized. The energization of Ythis relayunder theseA conditions, however, Willv have no-effect on the remainderofthe apparatus. `Whenthe braking bars reach their fullnonbrakingpositions, all

partsywillcoe restored tothe positions in 'which they .areshownpin thedrawings. 'Y i Y If;after lever L has beenmoved to its p5 posi- ,tion`so that the brakingbars are VVmoved to the position; in which they exerttheir maximum brakf y j g pressure for the new position of Ythelevenyjzhef.y

ing force, the Aoperator `moves lever L to itsfp2 position, valve V3 andrelay B will bothbecorne deenergized, and relay'C Ywillbecome energized,

-in the manner just described in describing the operation Vof theapparatus when lever L is movedl from its;p5 to its p1 positiony Underthese latter conditions, however, during the interval of time jrequiredY for relay BA to release its armature after. `theleverreachesitspz position, valve V2 Willbecome energized over ya circuit Vwhichpasses from battery Dv through wires '13 'I4 and 15, contact 36,2 ofleverL, Wire 88-line'wire 89, asymmetric unit 9;! in its low resistancedirection, contact 2e-,299 of. pressure responsive device P20-3, linewire 82,V line Wire 83,v and Wires l isthesam-e as that traced for valveV2 up to'V be vented from-cylinderA4 andv wires 84 and 85 back tobatteryD: will connect cylinder lOi will thenpecomeenergized wirefll,Vfrom which wirey this latter circuit passesfthrough Contact)metricdunit 8i@ in its low resistance.` direction,

winding Ziof rvalve V1, wires 8l adzBZ; l ne Wire as and wires stand t5back to .baaervD."Aftejrj valve Vl LV was moved' from its p1 lto its p2position.

The operation` of the `apparatus shown. in fig.;` ,Y 2'fo`r any othermovements 'of leverLnotspeci- @any described herein, winbjemderstobdjffhi the oregoing andf from anfzinspection 'fof thekdrawings without furthe'rdescription. 1 Y

It vwin be Seen from tnefcregoivng; 'that ouf v m F1a-.fitr 1 either theform of apparatus shown that vshownl in Fig. 2,l Whenleve. :'Li its p4or p5 position, fvalve V2 o'rvalve come energized and will admit fluid`low or the high pressure "system Iaccording armature of relay Cisthenpcked' uporlrel, leased.

It will also be seenv that relayC'Will be energized only when levervLoccupies its p1 or its p2 position so that if lever Lois moved quicklyfrom either its p1 or p5 position, relay characteristics Will valves 'V2and V3 from thelow pressure ysystem untilfthe pressure of the iluid incylinder 9` buildsup to substan-- becomes energized, y the.. applatuswill thenffunction inthe same manner aswlieri lever.`

or itsp2`positio'n to,` its pi', C, ,duev Vto its slow:releasingflAfunction to `Venergize the! in such manner that `iiuidA rst lbe,admittedvto the cylinderl 9Y of motor tially that ofthe loW pressuresystem, after which.l

fluid from they high pressure sy matically'admitted to cylinder 9.aconSiderable saving in the cost sure than it does to sure. I Y h,

Likewise it will benoted frornthe foregoing,

compress it to presposition to its p1` or p2 become Venergized and willconnectmotorgM with,

the iiuid in themotor to decrease to stem will be autoffl'.

a y of theid.; requiredA for theoperation of the car retarder," since itcosts less to compress iiuid toa'low jlgires.

6th;A

tially that of the low pressure systemv after which. Y

valve V1 vfluid to atmosphereuntil the pressure of 'the' Vwill becomevenergized and-Will vent l fluid'in thernotor has been reduced'to theproper..

further reduction inv operating cost.

AOne advantage of apparatus embodyingjour'.i f

invention is that we eiect the above described savings in fluid pressureby utilizing standard'A apparatus without the necessity orv complicatedvalves or other for anyspecial i, expensive parts,

Although we have herein shown andy describedA only two forms ofrailwaybraking apparatus Leni-. 1A

' ing fluid pressure to said bodying our invention, it is understoodthat various changes and modifications may be made therein within thescope of the appended claims without departing from the spirit andscope-of our invention.

Having thus described'our inventionwhat we claim is:

1. Railway braking apparatus comprising a braking bar extending parallelto a track rail, a fiuid pressuremotor for moving said braking bartowardsaid track rail Vto a braking position, a rst pipe connectedwith asource of relatively low pressure fiuid', a=second pipe connectedwith aVsource of relatively high pressure fluid, a slowreleasing relay, andmeans for at times supplymotor from said first or `said vsecond pipeaccording as the armature Y ofsaid relay is picked up or released. v 2,Railway7 braking apparatus comprising a braking .bar extending parallelto -a track rail, a fluid pressure motor for moving' said braking bartoward said track rail to a braking position, a first pipe connectedwith a source of relatively low pressure fluid, a second pipe connectedwith 25 a source of relatively high pressure fiuid, a slowreleasingrelay, manually controlled means for Venergizing said relay, meanseffective under certain conditions when said relay becomes deener'-gize'd ,for admitting fiuid pressure to said motor from said firstquired for said relay Vto release its armature, and 'means effective"after said relay has released its armature undersuch conditions foradmitting fluid pressure to said motor from said second l" plpe.

3. Railway braking apparatus comprising a braking bar extending a fiuidpressure motor for moving said braking bar toward said track rail to abraking position, a first pipe connected with a source of relatively lowpressurefluid', a second pipe connected with a source :of rrelativelyhigh pressure fluid, a manually operable lever having a plurality ofpositions each corresponding to a different brak- 45.. .mg force, a,slow-releasing n is moved quickly from `'motor from vsaid second pipe.

vpipe connectedrwith a source of relativelylow pressure fluid, a second'pipe connected with a source of relatively high pressure fluid, a firstmagnet valve effectivewhen energized for connecting said motorwithsaid-first pipe, a second Amagnet valve effective when energized forconnecting said motor with said second pipe, a slowreleasing relay,means for at times energizing said slow-releasing relay, and means attimes .effective when said relay becomes deenergized for energizingVsaid first a interval required for said relay tov release its armatureand for subsequently energizing said second valve. n Y

`5. Railway braking apparatus comprising a A"bri-,tiling bar movabletoward and away fromva pipe during the time interval reparallel to atrack rail,V

and non-braking posi- 4tions and biased toa non-braking position, afirst,

valve during the time track rail into braking and non-braking positionsand biased to a non-braking position, a first pipe connected with asource of relatively low pressure fluid,` a second pipe connected with asource of relatively high pressure fluid, a first magnet valve effectivewhen energized for Yconnecting said motor with said first pipe, a secondmagnet valve effective when energized for connecting said motor withsaid second pipe, a manually operable lever having an o position and an"on position in' which said braking bar is adapted to exert arelativelyhigh braking force, and a time element device controlled by said leverand effective `when said lever is moved from its ofi to itsfon positionfor successively energizing said first and second magnet valves in suchmanner that fiuid will be supplied to said fluid pressure motor fromsaid first pipe until the pressure of the fiuid in said motor builds upto substantially the pressure of the fluidin said first pipe after whichfluid from said second pipe will be supplied to said motor.

6. Railway braking apparatus comprising a braking bar movable toward andaway from a track rail into braking and non-braking positions, av fiuidpressure motor for moving said braking bar to its braking positions, afirst pipe connected with' a source of relatively low pressure fluid, asecond pipe connected with a source of relatively high pressure fluid, afirst magnet valve vfor connecting said motor with said first pipe, a

second magnet valve for connecting said motor with said second pipe, alever movable to two different positions and having one contact which'is closed in the one position and another contact which is closed in theother position, a relay provided with a circuit including one ofsaidcontacts, a circuit for said first magnet valve including the othercontact of said lever and a front contact of said relay, and a circuitfor said second magnet valve including said other contact of said leverand a back contact of said relay.

7. Railway braking apparatus comprising a braking bar movable toward andaway from a track railinto braking and non-braking positions, a fluidpressure motor for moving said braking bar to its braking positions, afirst pipe connected with a source of relatively low pressure fluid, asecond pipe connected with a source of relatively high pressure fluid, afirst magnetV valve for connecting said motor' with said first pipe, asecond magnet valve for connecting said motor with said second pipe, alever movable to two different positions andhaving one contact which isclosed Vin the one position and another .contact which is closed intheother position, a slow-releasing relay provided with a circuit inlcluding one of said contacts, a circuitfor said first magnet valveincluding the other contact of saidv lever and a front contact of saidrelay, and a circuit for said second magnet valve including-said othercontact of said lever and a back contact of said relay.

8. Railway braking apparatus comprising a braking bar movable toward andaway from a track rail into braking and non-braking posi-vr tions,afluid pressure motor for moving said Vbraking bar to its brakingpositions, a first pipe connected with a source of relatively lowpressure fluid, a second pipe connected with a source of relatively highpressure fluid, a first magnet valve for connecting said motor with saidfirst pipe, a second magnet valve for connecting said motor with saidsecond pipe, a lever movable toA two different positions and having onecontact pressure of the fluid in said motor exceeds a predeterminedvalue and with a normally open Vcontact which becomes closed if thepressure of the uid insaid motor increases a predetermined amount beyondthe pressure at which said normally closed contact becomes opened, afirst circuit for said first magnet valve including the other Contact ofsaid lever,'said normally closed contact of said pressure responsivedevice, and a front contact of said relay; a second circuit for said rstmagnet valve including the other contact of said lever and said normallyopen Contact of said pressure responsive device; and acircuit for saidsecond magnet valveincluding said other contact of said lever, saidnormally closed contact of said pressure responsive device, and aV yback contact of said relay.

9. Railway braking apparatus comprising a braking bar movable toward andaway from a track rail into braking and non-braking positions and biasedto a non-braking position, a iiuid pressure motor for moving saidbraking bar to its braking position, a first pipe connected with asource of relatively low pressure fluid, a second pipe connected with asource of'relatively high pressure iluid, means for at times supplyingfluid to said motor from said rst pipe and for at other times supplyinguid to said motor from said second pipe, a slow-releasing relay,manuallyv controlled means for energizing said relay, and meanseffective under certain conditions when said relay becomes deenergizedfor exhausting fluid from said motor into said iirst pipe until saidrelay releases its armature and for subsequently eX- hausting fluid fromsaid motor to atmosphere.

10. Railway braking apparatus comprising a braking bar movable towardand away from a trackrail into braking and non-braking positions andbiased to anon-braking position, a uid pressure motor for moving Saidbraking bar to its braking position, a rst pipe connected'with a sourceof relatively low pressure fluid, a second pipe connected with a sourceVof relatively high pressure iluid, a first magnet valve effective whenenergized for connecting said motor with said rst pipe, a second magnetvalve effective when energized for connecting said motor with saidsecond pipe, a third magnet valve effective when energized forconnecting said motor with atmosphere, manually controlled means forselectively energizing said rst and second valves to supply fluid tosaid motor, a time element device,

and means controlled in part by said time element device for at timessuccessively energizing said second and third valves to exhaust fluidfrom said motor.

11. Railway braking apparatus comprising a` braking bar movable towardand away from a track rail into braking and non-brakingpositions andbiased to a non-braking position, a iiuid pressure motor for moving saidbraking barto its braking position, a iirst `pipe connected with asource of relatively low pressure uid, a secondk pipe connected with asource of relatively high pressure fluid, a iirst magnet valve effectivewhen energized for connecting said motor with said rst pipe,va secondmagnet valve effective when ener'- gizedfor connecting said motor withsaid second pipe, a third magnet valve eiiective when energized forconnecting said motor with atmosphere, manually controlled means forselectively energizingsaid rst'and second valves to supply fluid to saidmotor, a time element device, vand means controlled in part by said timeelement device and effective under certain conditions after said Ymotorhas been supplied with iiuid from said'second pipe for selectivelyenergizing said second and third valves in such manner that fluid fromsaid motor will be vented into said iirst pipe for a suiiicient timeinterval t-opermit the pressure of the uid in the motor to decrease apredetermined amount after which fiuid will be vented to atmosphere.

v12. Railway braking apparatus comprising a braking bar movable towardand away from a track rail into braking and non-braking positions andbiased to a non-braking position, a fluid pressure motor for moving saidbraking bar to its braking position, a first pipe connected with asource of relatively low pressure fluid, a second pipe connected with asource of relatively high pressure fluid, a rst magnet valve effectivewhen energized for connecting said motor with said first pipe, va secondmagnet valveeiective whenenergized for connecting said motor with saidsecond pipe, a third magnet valve effective when energized'forconnecting said-motor with atmosphere, a lever having two positions andprovided with a first contact which is closed in the one position andwith a second and athird contact which are for said second magnet valveincluding said third contact. f

HERBERT L. BONE.. JOHN W. LOGAN, JR.

